"Teahitia is a submarine volcano in the Society Islands, whose summit reaches to within 1400 m of the surface, 40 km NE of the SE tip of Tahiti Island. Several seismic swarms in the 1980s included volcanic tremor that may have resulted from submarine eruptions (Talandier and Opal, 1984). Rocks dredged from the volcano in 1986 "exploded" when they reached the surface, suggesting recent lava extrusion that had not yet had time to equilabrate with pressure and temperature conditions on the submerged flanks of the edifice. Two hydrothermal fields each about 1km by 400 m in size that emitted low-temperature hydrothermal venting were discovered on the flanks of the volcano during submersible dives in 1986 and 1989." -Smithsonian Volcano Archive